The 400-or-so residents of Waltonville, Illinois, have been waiting almost a decade to cash in on the US ethanol boom. Now, that day may never come as a prolonged fuel glut alters the economics of corn for communities across the Midwest.

Waltonville had set aside 169 acres — a fifth of the town's land area — for a distillery to make 132 million gallons a year of the cornbased fuel additive.

At the time, government mandates were expanding use of ethanol in gasoline, and the project promised a boost to the local economy, including a new road.

But the property remains idle. Ethanex went bankrupt in 2008, along with many others across the Midwest — like Verasun Energy — that bet the wrong way on higher corn costs just as the recession sent fuel prices into a nosedive. Survivors kept expanding, boosting output to repay loans, and now there's more capacity than demand.

While the industry caught a break with record US harvests in 2013 and 2014, that only compounded the ethanol surplus while a surge in domestic oil supplies sent gasoline prices to a seven-year low.

"We overbuilt," said Ronald H Miller, who was the chief executive officer of Pekin, Illinois-based Aventine Renewable Energy when it went bankrupt in 2009 and is cofounder of the industry's biggest trade group, the Renewable Fuels Association. "We just went nuts. Plants were coming off the assembly line almost every week. We just built so rapidly."